Faced with such a problem: when I connect any external removable USB HDD or flash drive, Windows doesn’t assign a drive letter to it.
When a drive is connected, a message appears indicating that a new device is installed, the drive appears in the Device Manager, but is not displayed in the File Explorer.
Try to connect the USB flash drive directly to the computer (without the USB hub), check whether the power is on, and whether it is recognized on other computers. 4 of my 9 USB keys no longer mount on my computer but worked on my wife’s so I knew it was a Windows problem.
Gave up a year ago trying to solve the problem because none of the solutions on the web worked – and there are tons of them.
It seems that some feature of automatic detection of partitions on the external hard disks fails. First of all, make sure that the Virtual Disk service is running.
You can check the status of this service in the services management console (services.msc). When the automount is enabled, Windows automatically mounts file systems of new disks connected to the system and assigns drive letters to the partitions.
Also keep in mind that if there are several partitions on the USB flash drive, then Windows will only see the first partition.
The ability to create multiple partitions on removable USB drives appeared only in Windows 10 1703.
To make the drive available in the system, you must assign a drive letter through the Disk Management console each time manually.
To do this, open the Computer Management console (via the Win X menu) and go to the Storage section - Disk management.